The present invention relates to a spraying device for a lawn sprinkler. It is equipped with a circular base mount, a coupling board, a rotary sprinkling cover, a central flexible control piece and a water sprinkling blade assembly wherein the center of the circular base mount is disposed a water outlet having a securing hole in registration with the downward protrusion of the coupling board. The thermal meatball ring on the coupling board is used to make the coupling board secured to the rotary sprinkling cover by way of ultrasonic melting art The inner space of the rotary sprinkling cover is divided into an inner and outer sections. At the center of the rotary sprinkling cover is disposed a cavity for housing of the retaining part, a spring, a support member and a seal ring and a water outlet screen cap of the central flexible control piece. The retaining hole of the screen cap is provided with a rotary shaft for the water sprinkling blade assembly so as to make the blade assembly to be horizontally positioned in the cavity whereby the water can be sprinkled evenly and smoothly from the sprinkling ports without interference or interruption by the blade assembly.
Referring to FIG. 1, the first prior art lawn sprinkler 10 is made up of a base mount 11 and a spraying cap 12. A water inlet coupler 111 extends from one side of the base mount 11 and a circular platform 112 surrounded by a peripheral flange with a registration hole 113 defined at the center thereof and a water inlet 114 is disposed next to the registration hole 113. A retaining rib 115 having a retaining cut 1151. The spraying cap 12 is equipped with a plurality of spraying holes 121 in various patterns. A plurality of fixing legs 122 are disposed at the bottom of a central projection so as to register with the registration hole 113 of the base mount 11. The spraying holes 121 are provided with a stop wing 123 respectively distributed in radial directions. As the spraying cap 12 is rotated to one of the stop wings 123 and registered with the retaining cut 1151 of the retaining rib 115, one of the spraying holes 121 will become in alignment with the water inlet 114 so that water can be discharged from that spraying hole 121 as long as a water supply pipe is coupled with the water inlet coupler 11.
Such a prior art has a disadvantage given as follows: in particular, the center of the spraying cap 12 of the sprinkler 10 is not equipped with any spraying hole, so water can only be jetted or discharged by way of the peripherally disposed spraying holes 121. It is relatively simple and monotonous.
Referring to FIGS. 3, 4, the second prior art lawn sprinkler 20 comprises a round base mount 21, a coupling disc 22 and a rotary spraying cap 23 wherein the round base mount 21 has a central projected outlet 211 having a side coupler 212 in communication: with a water outlet 213 having a seal ring disposed therein. The central outlet 211 is provided with a fixing cavity 214 with which the retaining post 221 of the coupling disc 22 is registered. Next to the fixing cavity 214 is disposed a retaining post 215 based on a flexibly actuated plate. There are a plurality of round holes 222 defined around the periphery of the coupling disc 22. Each retaining recess 223 corresponding to the retaining post 215 is respectively disposed under the periphery of the round holes 222. A delicate protruded ring of melting connection 224 placed in alignment with the boundaries defined under the various spraying holes 231 is melted to created a closed wall to divide the internal space of the rotary spraying cap 23 into an inner and outer space. The center of the rotary spraying cap 23 has a centrally projected ball like pored sprayer 232. There are two closure discharge outlets 233 placed in opposition, the outer periphery are disposed spraying pores 234. The retaining post 221 is placed in the fixing cavity 214 with a proper clearance left therebetween so as to permit the coupling disc 22 to smoothly spin when the rotary spraying cap 23 is rotated in operation. As soon as the rotary spraying cap 23 is rotated to such a position that the surrounding walls of the ball like central pored sprayer 232 and one of the closure discharge outlets 233 comes into registration with the water outlet 213, water is then led to the inner space of the rotary spraying cap 23 and discharged via the central pored sprayer 232.
Such a second prior art lawn sprinkler 20 has the following disadvantage: the central pored sprayer 232 is integrally formed with the rotary spraying cap 23 and the top of the same is equipped with a ball shaped protrusion, resulting in the relatively bulky size in packing of the sprinkler in one aspect and the easy damage of the central pored sprayer 232 in transportation in another aspect.
Referring to FIGS. 5, 6, the third prior art lawn sprinkler 30 comprises a base mount 31, a rotary spraying cap 32 and a splattering blade assembly 33 wherein the base mount 31 has a flat top coupling face 311 with a central registration cavity 312. At one side of the flat top coupling face 311 is disposed a downwardly extended L-shaped inlet passage 313 having a connection head 3131 and on the other side is disposed a flexible spot protrusion 314. The rotary spraying cap 32 is provided with a protruded post 321 which is in registration with the registration cavity 312 of the base mount 31 so as to permit the rotary spraying cap 32 to be rotatable. On the top face of the rotary spraying cap 32 are disposed a plurality of spraying holes 322 of various patterns and a central pored spraying outlet 323 in communication with a closure spraying hole 324. The spraying holes 322 and the closure spraying hole 324 are in communication with the water outlet hole 325 which can be positioned in communication alignment with the inlet passage 313 when the rotary spraying cap 32 is rotated. There are a plurality of retaining cavities 326 corresponding to the water outlet hole 325 and registrable with the flexible spot protrusion 314. The shaft hole 331 of the blade assembly 33 is housed a bushing 332 having a pivot pole 333 which is engaged with the pivot hole 3231 of the central pored spraying outlet 323.
There are a number of disadvantages associated with the third prior art lawn sprinkler 30 given as follows:
1. The central pored spraying outlet 323 of the lawn sprinkler 30 is integrally formed with the rotary spraying cap 32 which has a ball shaped central surface. When the splattering blade assembly 33 is registered with the pivot hole 3231 defined on the spraying outlet 323, it will render the size of packing and delivery increased and the superficial face of the pored spraying outlet 323 is easily damaged as a result of impact
2. The splattering blade assembly 33 is mounted on top of the rotary spraying cap 32, as water is sprayed out of the spraying hole 322 via the sloped peripheral surface 3221, the sprayed water will be interfered by the blade assembly 33 in the area A as shown in FIG. 6, spoiling the spraying path of water.
3. The blade assembly 33 in rotation will be easily got stuck with the pivot pole 333 due to rotary friction, causing the rotary operation without smoothness.
Therefore, the primary object of the present invention is to provide a spraying device for a lawn sprinkler wherein the blade assembly can be retractably housed in a fixing cavity so as to allow the blade assembly to be received in flush with the top surface of the rotary spraying cap to reduce the packing size and to protect the blade assembly from damage as a result of impact.
Another object of the present invention is to provide a spraying device for a lawn sprinkler wherein the blade assembly can be selectively concealed in or popped out of a fixing cavity by means of a central flexible control piece so as to prevent the sprayed water from being interfered by the blade assembly in operation.
One further object of the present invention is to provide a spraying device for a lawn sprinkler wherein the splattering blade assembly is engaged with a pivot pole by way of a lubricant pad member so as to prevent the blade assembly from being in frictional contact with the pivot pole, rendering the rotary movement of the blade assembly smooth.